Question

The formulae of four organic compounds are given below:
A
C2H4
B
CH3COOH
C
CH3OH
D
CH,
(1) Which one of these compounds A, B, C or D is a saturated hydrocarbon?
(ii) Identify the organic acid and give its structural formula.
(ii) Which of the above compounds when heated at 443K in the presence of
concentrated H2SO4 forms ethene as the major product? What is the role played by
concentrated H2SO4 in this reaction? Also write the chemical equation involved.
(iv) Give a chemical equation when B and C react with each other in presence of
concentrated H2SO4. Name the major product formed and mention one of its
important use.​

Answer 1

A - Ethene $\rm(C_2 H_4)$

B - Ethanoic acid $\rm(CH_3 COOH)$

C - Ethanol $\rm(CH_3 CH_2OH \:\:or \:\: C_2 H_5OH)$

D - Methane $\rm(CH_4)$

(1)$\rm CH_4$(methane) is a saturated compound as it contains single bond.

Answer: option (D)

(2)$\rm CH_3COOH$(ethanoic or acetic acid)

structural formula: See the attachment

(3)$\rm CH_3 CH_2 OH$(ethanol) when reacted with Concentrated sulphuric acid at 443k forms an unsaturated compound - Ethene$\rm( C_2 H_4)$ along with water. This process is called dehydration.

$\rm H_2 SO_4$plays the role of a dehydrating agent

$\rm CH_3 CH_2 OH + H_2 SO_4 (conc) ---> C_2 H_4 + H_20$

(4) When B and C is reacted in the presence of concentrated $\rm H_2 SO_4$,it forms an ester. The process is called esterification.

$\rm CH_3 COOH + C_2 H_5OH ----> CH_3 COOC_2 H_5$

The product formed is Ethyl acetate

It is a sweet smelling substance. Therefore used in preparation of perfumes.